The present invention relates to a device for the blind coupling of supplies derived from generators or sources of fluidic, electrical or similar power, and which pass along inside a shaft or cylindrical sleeve which is static, to a receiving control mechanism such as, in the preferred application of the invention, a mechanism for controlling a system that controls the pitch of a turbomachine fan. The invention also relates to a fluidic assembly comprising a receiving control mechanism and a coupling device, and to a system for controlling the pitch of the blades of a turbomachine fan that comprises such a fluidic assembly.
More specifically, although not exclusively, the device is intended to be mounted in turbine engines with pairs of contra-rotating propulsion fans, known by their English name of “open rotor” or “unducted fan” engines. However, without departing from the scope of the invention, it could also be mounted on a turboprop that has a propeller for propulsion.
It is known that a turbine engine of the open rotor type mainly comprises, along a longitudinal axis and inside a fixed cylindrical nacelle borne by the structure of the aircraft (such as the rear part of an airplane fuselage), a “gas generator” part and a “propulsion” part. The latter part comprises two, coaxial and contra-rotating, fans, these respectively being the upstream (forward) and downstream (rear) fans which are driven, in opposite directions of rotation from one another, for example, by a suitable mechanical means driven by a power turbine situated at the exit of the gas generator part and the fan blades of which run substantially radially outside the nacelle.
To allow the turbine engine to operate optimally in the various phases of flight encountered, the contra-rotating fan blades are able to rotate about their respective pivot axes via a suitable pitch control system that allows the pitch of the blades to be varied during flight and on the ground, i.e., that alters the pitch of the fan blades. The blades may vary according to the system, from +90° to 30° for phases of flight, from +30° to −30° for phases on the ground and in reverse, and may have a rapid return to 90°, in the feathered position, in the event of in-flight malfunction (engine failure), when the blades are moved into a non-obstructing position relative to the direction of forward travel of the airplane and offer the least possible amount of drag. The “angular excursion” of the blades between the featured position and reverse position is thus of the order of 120°.